fix: enable UTF-8 console output for jbang.{cmd,ps1,sh} on Windows

docs/modules/ROOT/pages/troubleshooting.adoc

@@ -294,10 +294,17 @@ jbang --verbose script.java
 **Problem**: Various Windows-specific problems
 
 **Solutions**:
+
 1. **Path length limits**: Use shorter paths, enable long path support
 2. **Antivirus interference**: Add JBang directories to exclusions
 3. **PowerShell execution policy**: `Set-ExecutionPolicy RemoteSigned`
 4. **Line endings**: Ensure scripts use LF, not CRLF
+5. **UTF-8 console support**: JBang will automatically enable UTF-8 console support by executing command  `chcp.com 65001`. To disable this functionality, create environment variable `JBANG_WIN_UTF8` and set it to `false` and restart the shell session. `JBANG_WIN_UTF8` can be set to `false` from the command-line using the `setx` command:
++
+[source,bash]
+----
+setx JBANG_WIN_UTF8 false
+----
 
 === macOS Issues
 

src/main/scripts/jbang

@@ -133,11 +133,22 @@ execute_jbang() {
   fi
 
   if [ $err -eq 255 ]; then
-    eval "exec $output"
+    if [[ "$os" == "windows" ]] && [[ "$JBANG_WIN_UTF8" != "false" ]]; then
+      bash -c "$output"
+    else
+      # Jbang does not return from here ...
+      eval "exec $output"
+    fi
   elif [ -n "$output" ]; then
     echo "$output"
+    if [[ "$os" == "windows" ]] && [[ "$JBANG_WIN_UTF8" != "false" ]]; then
+      chcp.com $_original_cp > /dev/null
+    fi
     exit $err
   else
+    if [[ "$os" == "windows" ]] && [[ "$JBANG_WIN_UTF8" != "false" ]]; then
+      chcp.com $_original_cp > /dev/null
+    fi
     exit $err
   fi
 }
@@ -197,10 +208,20 @@ case "$(uname -m)" in
     ;;
 esac
 
+## Enable UTF-8 code page on Windows unless explicitly disabled
+if [[ "$os" == "windows" ]] && [[ "$JBANG_WIN_UTF8" != "false" ]]; then
+  _original_cp=$(chcp.com | grep -o '[0-9]\+')
+  chcp.com 65001 > /dev/null
+fi
+
 ## when using cygwin fall out to just running the bat file.
 if [[ $os == windows && -f "$abs_jbang_dir/jbang.cmd" && "$(uname -s)" == CYGWIN* ]]; then
   cmd /c "$(cygpath -m "$abs_jbang_dir"/jbang.cmd)" "$@"
-  exit $?
+  err=$?
+  if [[ "$os" == "windows" ]] && [[ "$JBANG_WIN_UTF8" != "false" ]]; then
+    chcp.com $_original_cp > /dev/null
+  fi
+  exit $err
 fi
 
 if [[ -z "$JBANG_JDK_VENDOR" ]]; then
@@ -277,3 +298,8 @@ if [[ -z "$binaryPath" ]]; then
 fi
 
 execute_jbang "$@"
+
+## Restore the original  Windows code page (if required)
+if [[ "$os" == "windows" ]] && [[ "$JBANG_WIN_UTF8" != "false" ]]; then
+  chcp.com $_original_cp > /dev/null
+fi

src/main/scripts/jbang.cmd

@@ -1,6 +1,14 @@
 @echo off
 SETLOCAL ENABLEEXTENSIONS ENABLEDELAYEDEXPANSION
 
+rem Set UTF-8 code page unless disabled
+if not "%JBANG_WIN_UTF8%" == "false" (
+    for /f "tokens=2 delims=:" %%G in ('chcp') do (
+        set /a _original_cp=%%G
+    )
+    chcp 65001 > nul
+)
+
 rem The Java version to install when it's not installed on the system yet
 if "%JBANG_DEFAULT_JAVA_VERSION%"=="" (set javaVersion=17) else (set javaVersion=%JBANG_DEFAULT_JAVA_VERSION%)
 
@@ -33,7 +41,11 @@ if "!binaryPath!"=="" if "!jarPath!"=="" (
     if !ERRORLEVEL! NEQ 0 ( exit /b %ERRORLEVEL% )
   )
   call "%JBDIR%\bin\jbang.cmd" %*
-  exit /b %ERRORLEVEL%
+  set ERROR=%ERRORLEVEL%
+  if not "%JBANG_WIN_UTF8%" == "false" (
+    chcp %_original_cp% > nul
+  )
+  exit /b %ERROR%
 )
 
 if not "!binaryPath!"=="" goto :run_with_cli
@@ -129,9 +141,16 @@ if %ERROR% EQU 255 (
 :break
   del /f /q "%tmpfile%"
   %OUTPUT%
-  exit /b %ERRORLEVEL%
+  set ERROR=%ERRORLEVEL%
+  if not "%JBANG_WIN_UTF8%" == "false" (
+      chcp %_original_cp% > nul
+  )
+  exit /b %ERROR%
 ) else (
   type "%tmpfile%"
   del /f /q "%tmpfile%"
+  if not "%JBANG_WIN_UTF8%" == "false" (
+    chcp %_original_cp% > nul
+  )
   exit /b %ERROR%
 )

src/main/scripts/jbang.ps1

@@ -203,5 +203,18 @@ if (-not $binaryPath) {
   }
 }
 
+if ($env:JBANG_WIN_UTF8 -ne "false") {
+    $Original_OutputEncoding = $OutputEncoding
+    $Original_ConsoleInputEncoding = [Console]::InputEncoding
+    $Original_ConsoleOutputEncoding = [Console]::OutputEncoding
+    $OutputEncoding = [Console]::InputEncoding = [Console]::OutputEncoding = [System.Text.UTF8Encoding]::new($false)
+}
+
 # Execute jbang
 Invoke-JBang -binaryPath $binaryPath -jarPath $jarPath -javaExec $JAVA_EXEC -args $args
+
+if ($env:JBANG_WIN_UTF8 -ne "false") {
+    $OutputEncoding = $Original_OutputEncoding
+    [Console]::InputEncoding = $Original_ConsoleInputEncoding
+    [Console]::OutputEncoding = $Original_ConsoleOutputEncoding
+}